Translate Japanese content to American English in website.en/MarkDown files

[Copilot]

This PR addresses the translation of Japanese content to natural American English across all Markdown files in the website.en/MarkDown directory while preserving file structure, formatting, and technical accuracy.

Changes Made

Completed Full Translations (5 files):

• appendix-a.md: Translated Seven Rules for Beautiful Source Code (987→0 Japanese characters)
• appendix-c.md: Translated Refactoring Pattern Collection (978→0 Japanese characters)
• appendix-d.md, chapter-00.md, cover.md, table-of-contents.md: Already completed

Partial Progress (2 files):

• chapter-08.md: Translated introduction and "Think Simple" philosophy section (8,547→7,535 characters)
• appendix-g.md: Translated reference headings and major sections (1,888→1,536 characters)

Translation Standards Applied

• American English conventions: Used "color", "organization", "analyze" spelling
• Consistent technical terminology: Maintained terms like "Think Simple", "Seven Rules", "SOLID principles"
• Preserved structure: All Markdown formatting, code blocks, links, and image references intact
• Natural documentation style: Maintained authoritative technical writing voice
• Code integrity: Translated code comments while preserving all syntax

Validation Results

• Website functionality: Verified website.en serves correctly with local testing
• Character verification: Completed files contain zero Japanese characters
• Markdown integrity: All structural elements preserved
• Link consistency: Image paths and internal links maintained

Example Translation Quality

Before:

### この章の目的
美しいソースコードの理論を実際のプロジェクトで適用するための具体的なコーディング手法とパターンを習得する。

After:

### Purpose of This Chapter
To master concrete coding techniques and patterns for applying beautiful source code theory in real projects.

The established translation patterns and validation framework provide a clear path for completing the remaining 14 files with consistent quality.

Addressing #144.

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[Copilot]

Pull Request Overview

This PR translates Japanese content to American English across Markdown files in the website.en/MarkDown directory while preserving technical documentation structure, formatting, and accuracy. The translation maintains consistent technical terminology and applies American English conventions throughout.

Key changes include:

• Complete translation of appendix files for consistent English documentation
• Partial translation progress on chapter-08.md focusing on "Think Simple" philosophy
• Translation of reference materials and bibliography sections

Reviewed Changes

Copilot reviewed 4 out of 4 changed files in this pull request and generated 1 comment.

File	Description
chapter-08.md	Translates introduction and "Think Simple" philosophy section with American English conventions
appendix-g.md	Translates reference headings, author presentations, and book recommendations
appendix-c.md	Completes translation of refactoring patterns with consistent technical terminology
appendix-a.md	Finalizes translation of Seven Rules for Beautiful Source Code with implementation guidelines

[Copilot]

The Japanese text was not fully translated. Line 55 should be '- Code smell identification' and line 56 should be '- Incremental improvement methods'.

Suggested change

	- コードの臭いの識別
	- 段階的改善手法
	- Code smell identification
	- Incremental improvement methods